Paraquat intoxication and hemocarboperfusion.

Abstract

In the northeast of Portugal, paraquat intoxication is common. We report 31 patients, admitted at our institution from April 1997 to June 2004, with suspected paraquat intoxication. Thirty cases had suicidal intention and all have ingested the toxic by mouth. Treatment consisted of skin and digestive decontamination with gastric washing and activated charcoal or Fuller's Earth. The first medical care was performed after 1 h 14 min at median [9 min-11 h 26 min]. By laboratory measurement (n=13) and/or clinical observation (n=11) it was possible to confirm the gastrointestinal absorption of paraquat for 24 patients (17 male-7 female; 49 +/- 17 years). The estimated ingested volume was higher for 15 non-survivors relatively to nine survivors (170 +/- 60 mL vs 25 +/- 10 mL; P<0,001). Initial serum paraquat of seven non-survivors was also higher than the serum level of six survivors (8.3 +/- 6.9 mg/L vs 0.4 +/- 0.3 mg/L; P < 0.01). Remarkably, all patients with serum paraquat higher than 1.7 ml/l did not survived. The paraquat urine level, simultaneous to the first serum determination, was higher for six survivors (38 +/- 37 mg/L) comparing with four non-survivors patients (465 +/- 536 mg/L; P<0.04). Hemoperfusion with activated charcoal was performed after December 1997 until June 2004 for 25 patients. Twenty of the 24 patients confirmed for paraquat intoxication were treated with this technique (12/15 of the non-survivors and 8/9 of the survivors; p=NS). Total number of sessions was identical (2.0 +/- 1.0 vs 1.5 +/- 1.2; P=NS), total time of hemoperfusion was higher (7 h 58 min vs 5 h 37 min; P=0.07) but the beginning of the first session was later (7 h 44 min vs 4 h 18 min; P=0.04) for the survivors. Clinical signs and laboratory analysis were collected at admission trying to detect markers of prognostic survival value. Hypernatremia, hypokaliemia, hyperglycemia and acute renal failure were more frequent for non-survivors (P<0.05) but the variable timing of the first laboratorial determination jeopardize our analysis, perhaps excluding acute renal failure. Rapid evolution to shock, lead to death for seven patients at the first day of admission and to another four deaths at the next day. Median survival of non-survivors was 1.2 days [0.1-13.2]. Evolution to pulmonary fibrosis for the nine survivors was not investigated (median follow-up: 14 days [2-1053]). Paraquat intoxication was highly lethal, leading to a 63% mortality rate of our patients. Hemoperfusion did not reveal any survival advantage for our patients.